Evolution of androgen-dependent brood cycling and the counter tactics

2014 Fiscal Year Final Research Report

• Project/Area Number: 24570029
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Ecology/Environment
• Research Institution: Nagasaki University
• Principal Investigator: TAKEGAKI Takeshi 長崎大学, 水産・環境科学総合研究科(水産), 准教授 (50363479)
• Co-Investigator(Kenkyū-buntansha): SOYANO Kiyoshi 長崎大学, 水産・環境科学総合研究科(水産), 教授 (80260735) ; KAGAWA Nao 近畿大学, 理工学部, 准教授 (80351568) ; AMIYA Noriko 北里大学, 海洋生命科学部, 講師 (20588503)
• Research Collaborator: MATSUMOTO Yukio ; IDE Yuki ; TERADA Ryusuke ; KAWAMINAMI Haruka
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 行動生態 / 進化 / 繁殖戦略 / 内分泌 / 魚類 / 子の保護 / ホルモン

Outline of Final Research Achievements

(1) The male sexual hormone testosterone, which controls brood cycling of Rhabdoblennius nitidus males, has no effect on the reduction of their immune function. The base sequence of a pituitary hormone prolactin (PRL), which is expected to promote parental care behavior in animals, was determined. (2) The nest egg-removal and -adding experiments strongly suggested that the presence of eggs in the nests is a key stimulus for the switch between reproductive phases by regulating plasma androgen levels of the males. (3) There was no significant relationship between male body condition and the number of cannibalized eggs. These results suggested that males cannibalize all eggs not to take nutritional resource but to delete eggs from the nests. (4) The effects of peptide hormones neuropeptide-Y (NPY) and orexin (ORX) on male feeding activity were examined to discriminate total-filial cannibalism from feeding behavior.

Free Research Field

行動生態学